Viadrus VIADRUS K 5, Operation And Installation Manual

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7 Commissioning
7.1 Connection to the heating system and watering the system
Before watering the heating system, it is necessary to clean properly this system, i.e. at least two times fill the
system with clean water and afterward drain it.
Water serving for watering the heating system has to be clean and colorless, without suspended
substances, without oil and without chemically aggressive substances. The heating system has to be filled
up with water, which complies with requirements of
Č SN 07 7401, and mainly its hardness mustn't exceed
the required parameters. Parameters of circulating and additive water have to comply:
Tab.
№ . 5 The maximum permissible values of heating water according to Č SN 07 7401
Recommended values
Hardness mmol/l 1
Ca
2+
mmol/l 0.3
Concentration of total Fe + Mn mg/l (0,3)*
*recommended value
WARNING!!! The manufacturer doesn't recommend using of antifreeze mixtures.
In case that water hardness doesn't comply with requirements, then it has to be modified. Even multiple heating
water with higher hardness will not prevent from excluding salts on the walls of the boiler drum. Sedimentation of 1
mm of limestone reduces the heat transmission from metal to water by 10 % in the given place.
During the heating season it is necessary to maintain the constant volume of heating water in the heating system
and be particular in the heating system is deaerated. Water from the boiler and the heating system mustn't be
discharged or withdrawn for using, except the necessarily needed cases, such as repairs and so on. Emptying
heating water and filling-up of new water increases a danger of corrosion and creation of water stone. If it is
necessary to add water into the heating system, please only add it to the cooled boiler, in order to prevent
bursting the section.
- During filling-up water into the boiler, the system has to be disconnected from the electric power supply
network.
- The air-relief valve on the boiler and on the heating system has to be opened and has to be workable.
- Adjust the expansion tank to the pressure by 10 kPa (0,1 bar) higher than the pressure required in the heating
system. Pressurize the system to the required pressure about 100 kPa (1 bar) and again deaerate. For the
purpose of watering, we recommend using a filter on the input into the heating system.
- The heating system has to have a sufficient number of deaerating points. A discharge valve has to be
mounted in the lowest place of the heating system.
- The expansion tank has the capacity of 10 liters, and its volume is enough for about 150 l of water in the
heating system.
- The system should be designed for the temperature gradient of 55/45 °C due to using the condensation.
- The condensing boiler can be also used for old gravity systems, which were over-dimensioned, and thanks to
it the condensation can be effectively used also for this system; however it is necessary to complete this
system with a corresponding expansion tank.
- The condensing boiler is equipped with a low-energetic pump with PWM control Wilo Yonos Para RS 15/7,5.
The modulation pump is controlled by the control unit of the boiler according to the selected strategy.
- The connection to the heating system, hot water and gas is to be performed through spherical valves.
Fig. № . 8 The dependence of dynamic pressure (head of delivery) and flow rate
U
s
a
b
le
o
v
e
rp
re
s
s
u
re
f
o
r
th
e
h
e
a
ti
n
g
s
y
s
te
m
[
k
P
a
]
The supply rate of heat transfer fluid - water [liter/hour]
The characteristics of the modulating pump and the boiler (usable dynamical
pressure)
Limitation of dynamical pressure through the bypass valve in the
boiler